https://www.biorxiv.org/content/10.1101/2021.06.17.448820v1
“Here, we show that the B.1.617 variants are highly fusogenic and form prominent syncytia. Bioinformatic analyses reveal that the P681R mutation in the spike protein is highly conserved in this lineage. Although the P681R mutation decreases viral infectivity, this mutation confers the neutralizing antibody resistance. Notably, we demonstrate that the P681R mutation facilitates the furin-mediated spike cleavage and enhances and accelerates cell-cell fusion.”
LOL! I don’t understand a lick of this either. It’s not just Greek to me, it’s insane!
I understood this...slightly
https://viralzone.expasy.org/5957?outline=all_by_species
Syncytia is formed by fusion of an infected cells with neighboring cells leading to the formation of multi-nucleate enlarged cells. This event is induced by surface expression of viral fusion protein that are fusogenic directly at the host cell membrane.
Syncytia can only happen with viruses able to directly fuse at the cellular surface without the need of endocytosis.